2. Pin Definitions

Name

No.

Type

Function

IO25

10

I/O

GPIO25, DAC_1, ADC2_CH8, RTC_GPIO6, EMAC_RXD0

IO26

11

I/O

GPIO26, DAC_2, ADC2_CH9, RTC_GPIO7, EMAC_RXD1

IO27

12

I/O

GPIO27, ADC2_CH7, TOUCH7, RTC_GPIO17, EMAC_RX_DV

IO14

13

I/O

GPIO14, ADC2_CH6, TOUCH6, RTC_GPIO16, MTMS, HSPICLK, HS2_CLK,

SD_CLK, EMAC_TXD2

IO12

14

I/O

GPIO12, ADC2_CH5, TOUCH5, RTC_GPIO15, MTDI, HSPIQ, HS2_DATA2,

SD_DATA2, EMAC_TXD3

GND

15

P

Ground

IO13

16

I/O

GPIO13, ADC2_CH4, TOUCH4, RTC_GPIO14, MTCK, HSPID, HS2_DATA3,

SD_DATA3, EMAC_RX_ER

SHD/SD2*

17

I/O

GPIO9, SD_DATA2, SPIHD, HS1_DATA2, U1RXD

SWP/SD3*

18

I/O

GPIO10, SD_DATA3, SPIWP, HS1_DATA3, U1TXD

SCS/CMD*

19

I/O

GPIO11, SD_CMD, SPICS0, HS1_CMD, U1RTS

SCK/CLK*

20

I/O

GPIO6, SD_CLK, SPICLK, HS1_CLK, U1CTS

SDO/SD0*

21

I/O

GPIO7, SD_DATA0, SPIQ, HS1_DATA0, U2RTS

SDI/SD1*

22

I/O

GPIO8, SD_DATA1, SPID, HS1_DATA1, U2CTS

IO15

23

I/O

GPIO15, ADC2_CH3, TOUCH3, MTDO, HSPICS0, RTC_GPIO13, HS2_CMD,

SD_CMD, EMAC_RXD3

IO2

24

I/O

GPIO2, ADC2_CH2, TOUCH2, RTC_GPIO12, HSPIWP, HS2_DATA0,

SD_DATA0

IO0

25

I/O

GPIO0, ADC2_CH1, TOUCH1, RTC_GPIO11, CLK_OUT1, EMAC_TX_CLK

IO4

26

I/O

GPIO4, ADC2_CH0, TOUCH0, RTC_GPIO10, HSPIHD, HS2_DATA1,

SD_DATA1, EMAC_TX_ER

IO16

27

I/O

GPIO16, HS1_DATA4, U2RXD, EMAC_CLK_OUT

IO17

28

I/O

GPIO17, HS1_DATA5, U2TXD, EMAC_CLK_OUT_180

IO5

29

I/O

GPIO5, VSPICS0, HS1_DATA6, EMAC_RX_CLK

IO18

30

I/O

GPIO18, VSPICLK, HS1_DATA7

IO19

31

I/O

GPIO19, VSPIQ, U0CTS, EMAC_TXD0

NC

32

-

-

IO21

33

I/O

GPIO21, VSPIHD, EMAC_TX_EN

RXD0

34

I/O

GPIO3, U0RXD, CLK_OUT2

TXD0

35

I/O

GPIO1, U0TXD, CLK_OUT3, EMAC_RXD2

IO22

36

I/O

GPIO22, VSPIWP, U0RTS, EMAC_TXD1

IO23

37

I/O

GPIO23, VSPID, HS1_STROBE

GND

38

P

Ground

Notice:

* Pins SCK/CLK, SDO/SD0, SDI/SD1, SHD/SD2, SWP/SD3 and SCS/CMD, namely, GPIO6 to GPIO11 are connected

to the integrated SPI flash integrated on the module and are not recommended for other uses.

2.3 Strapping Pins

ESP32 has five strapping pins, which can be seen in Chapter 6 Schematics:

Espressif Systems

4

ESP32-WROOM-32 Datasheet V2.9